Study on Roadbed 3D Model under the Condition of GIS

From the view of track 3D modeling technology and method,the key point and difficulty of the technology is the connection and integration of the roadbed 3D model with terrain 3D model.Under the basis of analyzing the current roadbed 3D modeling method,the paper studies the overlay of roadbed model and terrain model under the condition of GIS,puts forward the method of realizing roadbed 3D modeling and visualization by using the GIS control,and expounds the methods of realizing the key technologies.